Here's a compilation of all of the products offered by Overkill Motorsport for your 5.3 LS4 Impala SS.
:: Overkill Motorsports ::
www . ls4tune . com
Overkill tuning for the LS4 is offered through the Diablosport line of tuners. Not only do you get a great handheld, but you also get a premium LS4 tune from Overkill Motorsport rather than the generic preloaded tune. You'll get a 91/93 octane tune with 87 octane tuning also available, the ability to request to disable 4-cylinder Displacement On Demand/Active Fuel Management mode, significant revisions to the transmission to improve performance and life expectancy, and a horsepower gain of 15-20 on an otherwise stock car, with more significant gains with intake/exhaust upgrades. Custom tuning is available with datalogging and is no extra charge.
A module exchange service is still offered as well for 2007-2009 LS4s. Your Overkill tune gets flashed into a replacement module set, after being programmed with GM's latest factory calibration using GM's own programming system. These modules replace your current modules and voila you're tuned. The negative is this is a preset tune for your modifications, but the positive is pricepoint, a significant savings if you have only basic modifications to program for and are willing to send in your current computers for the deposit refund.
05-06 owners, we no longer offer the module exchange, but you can send in your modules for reprogramming, at the great pricepoint of $149! See our website for details.
One of the most significant LS4 modifications you can do is an intake manifold upgrade. The factory intake manifold is pinched at the inlet in a poor engineering effort by GM. Our solution is this Shutter intake manifold, which re-engineers a GM truck based intake manifold to fit the LS4, providing horsepower gains of 30 or more! This system comes complete with new fuel rails, fuel injectors, an adapter plate to bolt on your LS4 throttle body, new vacuum hoses, new gaskets and all stainless steel bolts. No modifications to the DoD system or valley plate are required, no fabrication except for a single hacksaw cut to the alternator bracket.
Overkill is the only company offering a bolt on LS4 intake manifold upgrade!
GM reuses the small V6 mass airflow sensor on the LS4 V8, and all other intakes on the market reuse this sensor with their kits. The Overkill intake uses a larger MAF sensor with a 4" inlet, that flows the airflow that a V8 needs. Dyno tested, it provided a 6 wheel horsepower gain on a typically modified LS4 with headers, tune and existing aftermarket intake system. Tuning is required but worthwhile! Retrofits are available to use this MAF with the K&N intake or CAI Inc intake.
See this youtube video for more info https://youtu.be/RFiCLx5aWqU
These are Brisk LGS spark plugs, designed in cooperation with Lamborghini (Brisk is their OE plug supplier). A patented surface fire spark plug, the spark happens deeper in the cylinder for a better burn, while its silver core is a better conductor than copper. You'll notice a smoother idle, better throttle response, and we've seen a consistent 3-4whp gain which is nothing to sneeze at at this pricepoint.
They are paired with the 8mm wires that GM upgraded to and used on the 6.2 Supercharged V8 platforms, which retrofit to the LS4.
This is a fully assembled, ready to install shift kit solution. A brand new housing using all brand new parts from GM encloses a TransGo shift kit, with a few custom Overkill revisions. By far the easiest way to install a shift kit, with no concerns about reusing worn parts, or assembly error.
Included is a Wix transmission filter kit, a new pan gasket, two new GM updated magnets for the pan and filter, and a Sonnax line retainer kit.